Unfortunately all their efforts didn't seem to change anything, and after six months they jointly agreed that it just was not working. So they sat down to begin to negotiate the details of the divorce. And that was almost exactly when things started to turn sour.

Their initially cordial discussion about the most reasonable way to split their assets quickly degenerated into a bitter and strategic battle. And, unfortunately for Harry, despite the fact that Patricia had never been involved in the commercial world and had practically no experience of negotiation techniques, she outclassed him immediately.

Before Harry even had time to think, Patricia employed three very effective negotiation strategies: the tactical demand list; the compromise hijack and process disruption.

The tactical demand list is simple. Suppose there are five things that you really want to get out of a negotiation. If you were buying a company this might be something like tax guarantees, environmental indemnification or extended warranty periods. In a divorce it's the house, the car, the CD collection and so on.

The way the tactical list works is that you don't ask just for the five things that you actually want, you also ask for a whole lot of other stuff that you don't want. Patricia, for example, included Harry's model train collection on her list, even though she had always despised it. Then, as the negotiation proceeds, you grudgingly give up some of your demands. This gives your opponent the impression that he is doing well, and enables you to claim you have made a lot of concessions.

But at the end of the day, you never have to give up the five important things. On the downside, though, this tactic does of course mean that the negotiation gets nastier and takes longer than it really ought to because so much time is spent discussing things that at least one of the parties couldn't care less about.

The compromise hijack is slightly more subtle. Eventually one side in any negotiation will offer some kind of compromise.

If you're not careful this compromise can be hijacked as follows.

The compromise: 'OK, I'll let you have the house but you've got to give me the apartment and the bank account,' Harry says.

The diversion: 'Thank you Harry, that's very kind of you to agree to let me have the house,' Patricia replies.

'You're welcome' Harry says, thinking things are going well, looking more cordial.

The hijack: 'OK, so now that we've agreed that I get the house, we still need to talk about the details. I can't let you have both the apartment and the bank account,' Patricia says.

So Harry either loses the house or ends up having to fight to get it back. And he's still negotiating everything else. The hijack is essentially taking the good parts of the compromise and rejecting the bad parts.

If this seems a little unfair, well it's nothing compared to the last and most effective of Patricia's tactics - the process disruption. The way this works is that Patricia, in addition to making the negotiation very difficult, makes it just as difficult to even have a negotiation. She refuses to return calls, she cancels appointments, and when she does meet Harry she continues to get angry and turn the conversation to personal matters, eventually storming out before any negotiation can take place.

This is not belligerence; it is a very sensible strategy. When Patricia eventually does agree to sit down at the negotiating table it is as though she has made a concession to Harry just by doing so. This places Harry in the position of having to make real concessions himself once the negotiation actually starts. She holds the threat over him the whole time that if he does not say the right thing in the negotiation, she will storm out and he'll be back to trying to get her to return his calls again.

This tactic only works in a situation in which the parties have nowhere else to go and where one party can give the impression that they don't care how long it takes. In commerce this is unusual, but in divorce it happens all the time.

So where are my friends Harry and Patricia at now? Harry explained his new negotiation tactic to me the other day. It's called capitulation. His goal is to make Patricia as happy as possible about his attitude and hope that this leads to them getting back together. He has discovered that being married to Patricia was nowhere near as bad as not being married to her.